1. Technical Field
The present disclosure relates generally to the field of combustion furnaces and methods of use to produce glass, and more specifically to methods and apparatus for making foamed glass using submerged combustion melters.
2. Background Art
High temperature foamed glass production currently utilizes conventional glass melting technologies and knowledge of control of sulfur gas compounds solubility in molten glass to produce glass with a large volume fraction of bubbles to give the glass objects thermal insulating properties. However, these glass products may suffer from offensive odors and may not have adequate high temperature properties.
Submerged combustion melting (SCM) involves melting glass batch materials to produce molten glass by passing oxygen, oxygen-air mixtures or air along with a fuel, typically liquid and/or gaseous fuel, into the glass batch, directly into a molten pool of glass usually through burners submerged in a glass melt pool. Part or all of the fuel can be solid organic fuel or waste, including ground fiber reinforced composite material, paper, wood, and the like. The introduction of high flow rates of oxidant and fuel into the molten glass, and the expansion of the gases cause rapid melting of the glass batch and much turbulence. However, one drawback to submerged combustion is the tendency of the molten glass to foam. Many methods of removing this foam, and the many bubbles of many sizes making up the foam, to make the molten glass usable in conventional glass forming processes have been proposed and many patent applications have been filed on these concepts and inventions. Many patents have issued.
For several years those involved in SCM technology, as evidenced by published patent applications and issued patents, have concentrated on ways of more quickly refining the foamy SCM molten glass. It would be an advance in the glass manufacturing art if foamed glass could be manufactured using a submerged combustion melter and methods. It would further be an advance in the art if foamed glass products and non-foamed glass products could be manufactured from the same molten batch from a submerged combustion melter.